The vehicle pictured here belongs to BimmerBoost user Omni who was kind enough to share the results of his ESS supercharged E39 M5 with us. Raising the boost to 9 psi with an 88mm pulley he was able to hit 516 wheel horsepower up from the 473 wheel horsepower he put down at lower boost with water-methanol injection. He is very happy with his kit and this is solid power. The only question we have to raise is how did ESS hit 501 wheel horsepower at 6 psi when actual customer dynos are showing it takes far more boost and are not able to replicate the claims?

This is a 2001 E39 M5 with 135,000 miles on it. Stock headers and a full exhaust with no cats:

I appreciate the interest guys. Funny as hell to sit down with my breakfast, pull up bimmerboost, and then see my car on the home page.
I will keep you posted with 1/4 mile times as soon as I head up there.

I would love to see you run some boosted E39s by RK Autowerks/Evolve Automotive! You seem to be making similar power to their Stage 2 kit.

Enjoy the power in safety!

First of all, congrats OP for making the power you did.

But you had to go from a 3.8" pulley to a 3.45 pulley? I really would advise against you running the 88mm pulley on your car. The fact you are seeing 6psi leads me to believe your boost reference isnt accurate. We have seen over about 100 dynos, and to hit 500whp, an S62 is producing an honest 8-9psi of boost. So dont believe that 6psi reading, you're really making 8-9.

OR

We can really analyze the situation if you post DRF files. I ask because there is a possibility you really are making 6psi, but the dyno correction factors make it seem as if you're making 500whp. The fact you said the car is running "rich" leads me to believe that is highly possible. If you have not changed your fuel pump, then i am leaning towards this. A car running 2 pulley sizes down is running dangerously lean, not the other way around. The tune is not capable of adapting for a change that significant, and the fuel pump cannot keep up either.

I appreciate the interest guys. Funny as hell to sit down with my breakfast, pull up bimmerboost, and then see my car on the home page.
I will keep you posted with 1/4 mile times as soon as I head up there.

The 3.6" produced a peak of 7. I Had to go down to the 3.48" in order to reach a peak of 9 at redline. This pressure reading has been verified with both a dyno's pressure sensor and my own on-board gauge. Stock fuel pump. Never leaner than mid 12 afr's.

Lostmarine,
Still haven't gone. Lots of street action though. Just picked me up a set of wheels for drag radials though. Will keep you posted.